Showing server-side validation messages next to problematic field

This however doesn't work for array-like fields, such as Multicheckbox fields (e.g. day of week), since the key served by the server (e.g. "repeat[weekly][dayOfWeek]") doesn't match the name of the field from the template (e.g. "repeat[weekly][dayOfWeek][]".
Other validation errors from a a form submission, not related to specific field, are shown at the top of the form.